A conventional solar cell structure with a p-type base has a negative electrode that is typically on the front side or sun side of the cell and a positive electrode on the backside. The solar cell has a carrier-collecting junction close to its front surface. The front surface is contacted with parallel fingers which are currently about 140 microns wide per finger. The fingers are connected by two bus bars that are perpendicular to the fingers. Typically, a five-inch square cell has about 55 fingers separated by about 2.1 mm spaces. The electric current collected for storage by the solar cell is gathered by metal contacts to a doped region on the front surface and by a second contact to the oppositely doped region on the back surface.
It is difficult to obtain very fine line and space resolution for the formation of the negative electrodes when applied by conventional patterning techniques such as screen printing, sputtering or chemical etching methods. The present invention will allow for the use of fibers or ribbons, wherein conductive metal particles are integrated into the fiber or ribbon, to form such electrodes on the front surface of the solar cell structure. The fibers or ribbons will allow narrower lines with increased height thickness which will increase the cell power by decreasing cell shadowing loss without increasing resistance of the lines. Currently shadowing loss accounts for about 9% loss in a solar cell structure. Narrower lines will substantially decrease such loss.
U.S. Pat. Nos. 3,686,036, 4,082,568, 4,347,262, and 4,235,644 disclose various solar cell devices and methods of manufacture.